1. Field of the Invention
The present invention relates to devices for cutting strip material, and more particularly to a strip cutting apparatus having an electronic controlled means for feeding the strip material to the blades of a scissor-like cutting action.
2. Description of the Prior Art
The need for an apparatus which will continuously feed and cut strip material into selected lenghts is long standing. In particular, manufacturers in the garment industry must accurately cut several different types of textile strip materials such as elastics, delicate, and hard materials at various angles and contours. Also, strip cutting machines must be easy to thread and must operate continuously at a rapid speed for best efficiency. Devices known in the prior art offer selectivity in regard to lengths of material cut but do not provide apparatuses which can be adjusted to effect accurate cutting of various types of materials. Also, when used to cut delicate fabrics, tearing may result as cutting apparatuses presently know cut by a chopping action wherein edges of the cutting blades remain in the same angular relationship during cutting.
A chop type cut as described above is provided by the apparatuses disclosed in U.S. Pat. No. 3,177,750 issued to E. Amemiya on Apr. 13, 1965 as well as in U.S. Pat. No. 2,865,448 issued to H. A. Mead et al on Dec. 23, 1958. This chop cut, while sucessful with paper and flexible plastics, is unsuitable for fabrics which will fray and tear.
Another feature of known devices is the use of a driven roller which is disposed beneath the strip material to be cut. This is typified in U.S. Pat. No. 2,701,013 issued to A. P. Klasing on Feb. 1, 1955 and in H. A. Mead et al and E. Amemiya. An idler roller above the strip material is urged toward the strip material forcing contact with the driven roller. The idler roller is withdrawn from the driven roller to terminate the feed of the strip material. Resultant of the force of gravity, a material having a very small degree or rigidity will frequently remain in contact with the driven roller and unwanted advancement and therefore an inaccurate length of strip material will be cut.
In H. A. Mead et al, E. Amemiya, and other devices known in the prior art the cutting stroke is effected by the urging of a cutting blade against the material to be cut by a spring. This spring exerts a constant amount of force. This constant force may be excessive for light materials and inadequate for heavy materials. In addition, as a result of the spring being subject to fatigue, the force of the cut varies with time. Retraction of the cutting blade is accomplished by a solenoid coupled to the blade by a lever and pivot assembly. The on time of the solenoid is much greater than the off time thereof as the solenoid is only deactivated to accomplish the cutting operation. When relatively long lengths of material are cut, the electricity required to keep the solenoid activated while the desired length is fed, generally causes an excessive cost. Also, as the solenoid is activated almost constantly, it is subject to wear and frequent failure.
Apparatuses presently known cannot be used as a parts cutter to cut notches into strip material or to separate parts joined by a binding material since the material to be cut must be threaded though the rollers from a position transverse to the longitudinal axis thereof as a result of the rollers being pivotally affixed on both free ends thereof within an enclosed housing.
The present invention overcomes the problems associated with the prior art by providing a strip cutting apparatus which includes means for cutting strip materials of various weights and elasticity by a scissor-like action, feed means having the driven portion thereof above the strip material to be cut, means for effecting a cutting stroke, the duration of which can be varied, means for the insertion of strip material into the feeding means from a position adjacent the lateral ends of the rollers thereof, and means for effecting the scissor-like cutting action by the activation rather than deactivation of a solenoid or the like.